Trends in depressive symptom burden among older adults in the United States from 1998 to 2008.

Abstract

Diagnosis and treatment of depression has increased over the past decade in the United States. Whether self-reported depressive symptoms among older adults have concomitantly declined is unknown. To examine trends in depressive symptoms among older adults in the US between 1998 and 2008. Serial cross-sectional analysis of six biennial assessments. Health and Retirement Study (HRS), a nationally-representative survey. PATIENTS OR OTHER PARTICIPANTS Adults aged 55 and older (N = 16,184 in 1998). The eight-item Center for Epidemiologic Studies Depression scale (CES-D8) assessed three levels of depressive symptoms (none = 0, elevated = 4+, severe = 6+), adjusting for demographic and clinical characteristics. Having no depressive symptoms increased over the 10-year period from 40.9% to 47.4% (prevalence ratio [PR]: 1.16, 95 % CI: 1.13-1.19), with significant increases in those aged ≥ 60 relative to those aged 55-59. There was a 7% prevalence reduction of elevated symptoms from 15.5% to 14.2% (PR: 0.93, 95 % CI: 0.88-0.98), which was most pronounced among those aged 80-84 in whom the prevalence of elevated symptoms declined from 14.3% to 9.6%. Prevalence of having severe depressive symptoms increased from 5.8% to 6.8% (PR: 1.17, 95 % CI: 1.06-1.28); however, this increase was limited to those aged 55-59, with the probability of severe symptoms increasing from 8.7% to 11.8%. No significant changes in severe symptoms were observed for those aged ≥ 60. Overall late-life depressive symptom burden declined significantly from 1998 to 2008. This decrease appeared to be driven primarily by greater reductions in depressive symptoms in the oldest-old, and by an increase in those with no depressive symptoms. These changes in symptom burden were robust to physical, functional, demographic, and economic factors. Future research should examine whether this decrease in depressive symptoms is associated with improved treatment outcomes, and if there have been changes in the treatment received for the various age cohorts.